DE3226112A1 - Method and device for rapid thin layer chromatography - Google Patents

Abstract

This method and its device for carrying out rapid TLC analyses is effected using a strip for transferring mobile phase by means of a magnetic field or a mechanical force to the TLC layer linearly. The transfer of mobile phase to the TLC layer can be ended at any time and shifted to any other desired site of the TLC layer and development in this new site of the absorbent layer can thus begin again as quickly as possible; this can be carried out any desired number of times and also with various mobile phase.

Description

Method and device for fast thin-layer chromatography

graphie Thin-layer chromatography, or TLC for short, is known as the most widespread and fast analytical separation method known.

After applying the sample to the TLC layer (stationary phase ), takes place with a solution (flow agent or mobile phase) through the capillary forces a chromatographic separation of the sample. Thereby the individual substances separated from each other at different distances.

Since the flow rate increases with increasing distance becomes slower, is the separation of the substances R which are in the vicinity of the solvent front are in a slower This disadvantage limits the possible uses of the Thin layer chromatography in general.

The flow agent supply to the TLC layer can be punctiform at the Circular technique, ring-shaped for the anti-circular technique or linear done with the most commonly used linear DC.

All previous linear superplasticizer transfers to the DC layer always take place from the edge of the plate, either by immersing the plate in the solvent or by supplying superplasticizers with a superplasticizer (paper etc.) (CH-PS 364130 and PS 450005) as well as with a capillary gap (CH-PS 2818576).

With none of these DC chambers could. the supply of solvent is variable can be done linearly at any point on the DC layer and thus the development accelerate.

The unevenness of the DC layer complicates resp. make one impossible uniform, linear wickless flow of solvent and lead to damage the DC layer.

Only when using so-called surface dispensers for DC (CH-PS 8570/79 ) this does not damage the DC layer, but the wide contact area between the surface dispenser and the DC layer makes it impossible to separate rows of spots lying close together.

The method described in the literature (Anal. Chem. 1981, 53,714716), uses a syringe to relocate the flow of solvent for rapid DC separation; but this leads to geometrical distortions of the substance stains as well as the quantitative ones Evaluation, as the superplasticizer supply can only succumb to purite form.

Therefore a syringe (for a 20cm wide TLC plate, more than 30 syringes are required! ) for the superplasticizer supply and all syringes are provided with a control mechanism.

The present invention has for its object a method for Perform a fast thin-layer chromatography to create those with little outlay in terms of apparatus and, with low consumption of superplasticizer, one in terms of time and location allows variable linear flow of solvent.

According to the invention, this object is achieved by a method which the flow agent with a porous strip on the DC layer linearly is directed in such a way that the flow of solvent can be interrupted at any time or can be done new and at the same time in two opposite directions. This also after a position shift in the flow of solvent to the DC layer in relation to one another. This enables a linear flow medium supply that is variable in terms of time and location across the entire width and at any point on the TLC plate, which can be any can take a long time. This also avoids the temporal disadvantage of the DC in the case of longer flow routes be resolved. This with minimal consumption of solvent and with the possibility also for reciprocal flow of solvent on the TLC layer.

Using the following description and the attached drawings the inventive method and exemplary embodiments of the device for Implementation of the procedure explained.

In the drawing: FIG. 1 shows a plan view of a DC chamber linear, variable fluid supply, which is magnetically actuated Fig. 2 shows a cross section through the dismantled chamber of FIG. 1; FIG. 3 shows a view (a ) and a cross section (b) of the strips for the magnetically actuated fluid supply Fig. 4 a top view (a) and a cross section (b) of the strips for the mechanical actuated flow medium supply Fig. 5 shows a cross section (a) of the strips in the flow medium container before the mechanically operated flow agent feed and after the flow agent has been fed in represent.

Identical elements are identified identically in the drawings.

In FIGS. 1 and 2 there is a chamber for temporal and spatial variable flow agent supply, which in the height of approx. 0.5mm through intermediate insert variable, super-narrow "sandwich" TLC chamber shown; therefore there are none Saturation problems with the gas phase.

The removable holding frame (1) for TLC plates (5) with cover glass (.2) closed, is tight over the entire length of the chamber base plate (6) movable. The magnet holder (14) with the magnet (15) is removable and simply positioned by two guides. The length of the displacement of the holding frame (1) can be adjusted by means of two measuring rods (3) attached on both sides. The chamber is provided with a fixed foot (12) and two adjustable feet (13) and can be adjusted horizontally using a spirit level.

A flux transfer strip (11) on an iron beam (10) is pushed on, is inserted into the fluid container (9). Thereafter the fluid is fed through the line (8) into the fluid container with a syringe (7) (9) injected into the chamber base plate (6); The samples to be analyzed can be applied in two rows on the TLC layer (also in the middle of the TLC plate) will. The plate (5) is finally pushed into the holding frame (1) and held with a spring system (4).

The holding frame (1) together with the TLC plate (5) is placed on the base plate (6) in place and positioned as required.

After inserting the magnet holder (14), the iron bar ( 10) including the strip (-11) lifted and pressed onto the Schiht (5); Consequently the development begins.

After removing the magnet holder (14) the iron beam falls: ( 10) together with the strip (*) back into the solvent container (9.) and with it the development is interrupted.

After moving the plate frame (1) to another waincht Position and the subsequent placement of the magnet holder (14) begins this point and this at the same time in the entire width of the sorbent layer as well in two opposite directions, the development again new and fastest This can also be done several times on different points of the sorption layer and this in each case can also be carried out with various superplasticizers.

The remaining residues of the respective solvent in the solvent container (9, 19) can advantageously be emptied with a syringe (7) and then emptied be sucked off with vacuum.

The vapors of the solvent can be extracted in the same way. Since this linear transfer of flow agent inevitably also leads to a focusing effect which leads to separate substance ranks; this takes place after the superplasticizer has been laid from one side of the row of substance stains to the other in a matter of seconds.

Each subsequent development can be the same or a different one Flux opposite to the previous direction of development.

In Fig. 5 a and b is the mechanically operated fluid transfer with a thick strip (Fig. 4 - 17) and the vertically movable fluid trough (19). The flow agent is supplied to the DC layer (5) via an edge (18) of the strip (17) when the flow agent trough (19 ).

In both examples described, the parts can be reversed be; the chamber shown in FIGS. 1 and 2 can also consist of a fixed holding frame (1) and a sliding base plate (6). The one in Fig. 5 The container (19) shown in a and b can be fixed and the TLC plate (5) together with the frame be vertically movable.

The temporally and spatially variable supply of superplasticizer on any Place (s) of the sorption layer is called "SEQUENCE - DC technology".

This DC chamber can preferably be made of anodized aluminum, glass or can also be made of other material coated with PTFE.

This type of flow agent supply to the separating layer can also be used with The electrophoresis can be used when the flow agent trough (9) together with the supply line (8) Insulated enough from the chamber - and the chamber made of plastic or glass as well as other electrically non-conductive materials.

This means that the sequence DC technique can also be used in electrophoresis find new uses.

Detection of the separation can also be easy during development with a W lamp built into the base plate (6).

Some application examples of the 1I SEQUENCE - DC t technology - two pre-separated rows of substances can be transported from one another in a matter of seconds - The development begins in two opposite directions at the same time; this makes possible a double sample application, respectively.

a double plate utilization - the samples can can also be applied in several rows.

- After the intermediate drying, you can also use another place Develop with another superplasticizer.

- die.Gemische of hydrophilic and lipophilic substances can with two fluxes in two opposite directions of development simply from each other be separated.

- the two-dimensional development is also easy to carry out.

- The separate, diffuse rows of spots can be focused in a matter of seconds - the entire length of the TLC plate layer can be used to the maximum.

Claims (9)

PATENT CLAIMS 4). The method and apparatus for carrying it out the - rapid thin-layer chromatography - separation is characterized by that the flow of solvent to the sorption layer is linear and at the same time in two opposite directions and this at the same time across the entire width and on can take place at any point and is variable over time. 2.- Superplasticizer is supplied to the TLC layer with a, on a ferrous bar (10 5 pushed-on strip (11) and one on it laid magnet. 3.- Adding solvent to the DC layer is done mechanically Pressure one of the absorbent strips onto the sorbent layer. 4.- The flow medium is fed into the flow medium container (9) from the outside through the supply line (7 and 8) even when the chamber is closed. 5.- A UV detector lamp is built into the base plate. The base plate (6) of the chamber (Fig. 1 and 2) is for the holding frame (1) or the holding frame (1) can be moved to the base plate (6). 7.- The displacement of the holding frame (1) in relation to the base plate is programmable in terms of time and location, mechanically and electronically. 8.- The flux transfer strip (17 is in a separate movable fluid trough (19) inserted. 9.- The fluid is transferred to the sorption layer by the pressure on the holding frame (1) of the TLC plate (5).